Engine Coolant Temperature Sensor Guide for 2015-2023 Chevrolet Silverado 1500
An essential guide to diagnosing and replacing the engine coolant temperature sensor on your Silverado 1500.
- A bad ECT sensor can mimic other problems; common symptoms include a dead temp gauge, fans running constantly, and poor fuel economy.
- The P0128 code is very common but is often caused by a faulty thermostat, not the sensor itself.
- The sensor is located on the driver's side front of the engine near the thermostat housing and is relatively easy to replace with a 19mm deep socket.
- For best results, choose an OEM (ACDelco, Delphi) or a reputable aftermarket brand (NGK, Standard, Walker) to ensure reliability.
Is Your Silverado's ECT Sensor Failing?
A bad Engine Coolant Temperature (ECT) sensor can cause a range of confusing problems. Because it provides key data to the engine computer, a faulty sensor can make the truck behave as if it has more serious engine trouble. Recognizing the signs early can save you from a wrong diagnosis and unnecessary repairs.
Key Symptoms of a Bad ECT Sensor:
- Check Engine Light: This is often the first sign. The sensor may trigger codes like P0117, P0118, or P0128. 🎬 Watch: EricTheCarGuy explains what P0118 means for your engine.
- Inaccurate Temperature Gauge: The gauge on your dashboard might stay at its lowest reading (160°F), jump around wildly, or show the engine is overheating when it's not.
- Cooling Fans Run Constantly: The fans may run at full speed all the time, even when the engine is cold or after the truck is turned off. This happens because the computer, receiving no signal or a bad one, defaults to emergency mode to prevent overheating.
- Poor Fuel Economy: If the sensor incorrectly tells the computer the engine is always cold, the computer will keep the fuel mixture rich, burning more gas than necessary.
- Black Smoke from Exhaust: A constantly rich fuel mixture can result in unburned fuel exiting through the exhaust, appearing as black smoke.
- Rough Idle or Poor Performance: The engine may run rough, hesitate, or feel sluggish because the fuel mixture and ignition timing are incorrect for the actual engine temperature.
Don't Mistake It for a Bad Thermostat
Many symptoms of a bad ECT sensor overlap with a failing thermostat, especially the P0128 trouble code (Coolant Temperature Below Thermostat Regulating Temperature). A thermostat stuck open is a very common issue on these trucks and will prevent the engine from reaching proper operating temperature, triggering the same code. A GM Technical Service Bulletin (TSB) also notes that a software glitch can cause a false P0128 code, which requires an ECM reprogram to fix. Always diagnose properly before replacing parts.
🎬 See this DIY fix for the common P0128 fault code.Choosing the Right Aftermarket ECT Sensor
When it comes to electronics, quality matters. While you can save money with aftermarket parts, choosing a reputable brand is key to avoiding a repeat failure.
- Tier 1 - OEM & Premium Aftermarket: ACDelco GM Genuine is the original part your truck came with. Delphi is also a major OEM supplier with a strong reputation. These are your safest bets for fit, function, and longevity. ACDelco also offers a high-quality aftermarket "Professional" line (now called Gold).
- Tier 2 - Reputable Aftermarket: Brands like NGK/NTK, Standard Ignition (SMP), and Walker Products are well-known in the aftermarket and produce reliable sensors that meet or exceed OEM specifications. They offer a good balance of price and quality.
- Tier 3 - Value Brands: Brands like Four Seasons, Facet, and others offer the lowest price. While they can be a good budget option, some user reviews mention a higher chance of premature failure or incorrect readings. For a critical sensor like this, spending a few extra dollars for a higher-tier brand is often a wise investment.
Pro Tip: Location and Installation
On the 2015-2023 Silverado 1500 with V8 engines (5.3L, 6.2L), the ECT sensor is located on the front of the engine, on the driver's side, right next to or just below the thermostat housing where the upper radiator hose connects. It's a small sensor with a single electrical connector. The job is straightforward and can be done with basic tools in about 15-30 minutes. You will need a 19mm deep socket. Always perform this replacement on a cold engine to avoid being burned by hot coolant. Expect a small amount of coolant to spill when you remove the old sensor.
Cost of Replacing the ECT Sensor
| Part Type | Price Range |
|---|---|
| New Aftermarket | $15.70 - $50.56 |
| New OEM (ACDelco GM Genuine) | $25 - $60 |
| Shop Labor | $80 - $233 |
Frequently Asked Questions
Where is the ECT sensor on my 2015-2023 Silverado?
For V8 models, it's on the driver's side front of the engine, near the thermostat housing where the large radiator hose connects. You may need to remove the plastic engine cover and air intake tube for easier access.
Can I drive my truck with a bad ECT sensor?
It is not recommended for long distances. A bad sensor can cause the engine to run poorly, use excess fuel, and potentially lead to overheating if the cooling fans don't turn on. If the temperature gauge is not working, you have no way of knowing if the engine is actually overheating, which can cause severe damage.
Why do some Silverados have two temperature sensors?
Some models have two sensors in the same general area. One sends temperature information to the gauge on your dashboard, while the other sends data to the engine computer (ECM) for managing the engine. The sensor that communicates with the ECM is the one that affects engine performance and triggers fault codes.
Do I need to use thread sealant on the new sensor?
Yes, it is recommended to use a small amount of thread sealant or Teflon tape on the threads of the new sensor to prevent coolant leaks. Be careful not to get any sealant on the tip of the sensor, as this can interfere with its ability to read the temperature correctly.
Are there any recalls for the ECT sensor on the Silverado?
No, there are no specific recalls for the Engine Coolant Temperature sensor on the 2015-2023 Silverado 1500. Searches of NHTSA data found recalls for other components, but not the ECT sensor itself. However, there are several Technical Service Bulletins (TSBs) related to the P0128 code, which can be caused by the thermostat or an ECM software issue.
Helpful Videos
Technical Specifications
OEM Part Numbers: 12608814 12674639 12650595
The sensor is a thermistor, meaning its electrical resistance changes with temperature. It typically has a 2-pin connector and threads into the engine block or thermostat housing. A 19mm deep socket is required for removal and installation.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Chevrolet Silverado 1500: